Mass Wasting

The large-scale movement of waste materials, derived from weathering of bedrock, down a slope, is known as mass wasting or mass movement. Water, wind, and glaciers are the main agents of mass wasting. There is rapid movement of rocks on steep slopes. Mass movements can be classified into slow and rapid movements:


Types of Mass Wasting


Slow Movements

  • Slow movements can be further categorized into creep and solifluction.
  • The slow downhill movement of debris is called soil creep. Fine weathered rock debris is known as soil creep, while unweathered blocks of rocks are known as rock creep.
  • When water or wet soil forms clay and moves down the slope as a viscous liquid, it is called solifluction.

Rapid Movements

  • Landslides: This is the most common of all the mass movements. When the surface of the rock breaks off, the rock is displaced from its place and a heavy movement of rock and mud takes place. The downwards slope of the rock takes place in two main ways:
    • Fall: Fragments of rocks fall through steep slopes
    • Slide: A rock along with mud comes down from a slope in a fixed path
  • Earth Flow: Fine-grained materials which have been saturated with water come down a slope because of the pull of gravity. Earth flow generally occurs in areas which have alluvial soils or are in hilly regions.
  • Mud Flow: Water flows with many particles such as silt down a slope. In mudflow, the quantity of water is more than in Earth flow. It generally occurs in areas where vegetation is sparse and slopes are steep.
  • Sheet Wash: The entire piece of land is covered with a thick layer of mud, soil and water. This occurs in the absence of natural vegetation. Many parts of the world have been affected because of sheet wash.

Mass wasting also creates various landforms. Landslides on the Himalayan hillslopes have created many lakes. Some other landforms created as a result of mass wasting are ripples, escarpments, terraces, meanders, and scars.


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